SNAS835 September   2022 LMK5B33414

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Diagrams
    7. 6.7 Typical Characteristics
  7. 7 Parameter Measurement Information
    1. 7.1 Differential Voltage Measurement Terminology
    2. 7.2 Output Clock Test Configurations
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
      1. 8.2.1 PLL Architecture Overview
      2. 8.2.2 DPLL
        1. 8.2.2.1 Independent DPLL Operation
        2. 8.2.2.2 Cascaded DPLL Operation
        3. 8.2.2.3 APLL Cascaded With DPLL
      3. 8.2.3 APLL-Only Mode
    3. 8.3 Feature Description
      1. 8.3.1  Oscillator Input (XO)
      2. 8.3.2  Reference Inputs
      3. 8.3.3  Clock Input Interfacing and Termination
      4. 8.3.4  Reference Input Mux Selection
        1. 8.3.4.1 Automatic Input Selection
        2. 8.3.4.2 Manual Input Selection
      5. 8.3.5  Hitless Switching
        1. 8.3.5.1 Hitless Switching With Phase Cancellation
        2. 8.3.5.2 Hitless Switching With Phase Slew Control
        3. 8.3.5.3 Hitless Switching With 1-PPS Inputs
      6. 8.3.6  Gapped Clock Support on Reference Inputs
      7. 8.3.7  Input Clock and PLL Monitoring, Status, and Interrupts
        1. 8.3.7.1 XO Input Monitoring
        2. 8.3.7.2 Reference Input Monitoring
          1. 8.3.7.2.1 Reference Validation Timer
          2. 8.3.7.2.2 Frequency Monitoring
          3. 8.3.7.2.3 Missing Pulse Monitor (Late Detect)
          4. 8.3.7.2.4 Runt Pulse Monitor (Early Detect)
          5. 8.3.7.2.5 Phase Valid Monitor for 1-PPS Inputs
        3. 8.3.7.3 PLL Lock Detectors
        4. 8.3.7.4 Tuning Word History
        5. 8.3.7.5 Status Outputs
        6. 8.3.7.6 Interrupt
      8. 8.3.8  PLL Relationships
        1. 8.3.8.1  PLL Frequency Relationships
          1. 8.3.8.1.1 APLL Phase Detector Frequency
          2. 8.3.8.1.2 APLL VCO Frequency
          3. 8.3.8.1.3 DPLL TDC Frequency
          4. 8.3.8.1.4 DPLL VCO Frequency
          5. 8.3.8.1.5 Clock Output Frequency
        2. 8.3.8.2  Analog PLLs (APLL1, APLL2, APLL3)
        3. 8.3.8.3  APLL Reference Paths
          1. 8.3.8.3.1 APLL XO Doubler
          2. 8.3.8.3.2 APLL XO Reference (R) Divider
        4. 8.3.8.4  APLL Phase Frequency Detector (PFD) and Charge Pump
        5. 8.3.8.5  APLL Feedback Divider Paths
          1. 8.3.8.5.1 APLL N Divider With SDM
        6. 8.3.8.6  APLL Loop Filters (LF1, LF2, LF3)
        7. 8.3.8.7  APLL Voltage-Controlled Oscillators (VCO1, VCO2, VCO3)
          1. 8.3.8.7.1 VCO Calibration
        8. 8.3.8.8  APLL VCO Clock Distribution Paths
        9. 8.3.8.9  DPLL Reference (R) Divider Paths
        10. 8.3.8.10 DPLL Time-to-Digital Converter (TDC)
        11. 8.3.8.11 DPLL Loop Filter (DLF)
        12. 8.3.8.12 DPLL Feedback (FB) Divider Path
      9. 8.3.9  Output Clock Distribution
      10. 8.3.10 Output Channel Muxes
      11. 8.3.11 Output Dividers (OD)
      12. 8.3.12 SYSREF/1-PPS
      13. 8.3.13 Output Delay
      14. 8.3.14 Clock Outputs (OUTx_P/N)
        1. 8.3.14.1 Differential Output
        2. 8.3.14.2 LVCMOS Output
        3. 8.3.14.3 SYSREF/1-PPS Output Replication
        4. 8.3.14.4 Output Auto-Mute During LOL
      15. 8.3.15 Glitchless Output Clock Start-Up
      16. 8.3.16 Clock Output Interfacing and Termination
      17. 8.3.17 Output Synchronization (SYNC)
      18. 8.3.18 Zero-Delay Mode (ZDM)
      19. 8.3.19 Time Elapsed Counter (TEC)
        1. 8.3.19.1 Configuring TEC Functionality
        2. 8.3.19.2 SPI as a Trigger Source
        3. 8.3.19.3 GPIO Pin as a TEC Trigger Source
          1. 8.3.19.3.1 An Example: Making a Time Elapsed Measurement Using TEC and GPIO1 as Trigger
        4. 8.3.19.4 TEC Timing
        5. 8.3.19.5 Other TEC Behavior
    4. 8.4 Device Functional Modes
      1. 8.4.1 Device Start-Up
        1. 8.4.1.1 ROM Selection
        2. 8.4.1.2 EEPROM Overlay
      2. 8.4.2 DPLL Operating States
        1. 8.4.2.1 Free-Run
        2. 8.4.2.2 Lock Acquisition
        3. 8.4.2.3 DPLL Locked
        4. 8.4.2.4 Holdover
      3. 8.4.3 PLL Start-Up Sequence
      4. 8.4.4 Digitally-Controlled Oscillator (DCO) Frequency and Phase Adjustment
        1. 8.4.4.1 DPLL DCO Control
          1. 8.4.4.1.1 DPLL DCO Relative Adjustment Frequency Step Size
          2. 8.4.4.1.2 APLL DCO Frequency Step Size
      5. 8.4.5 APLL Frequency Control
      6. 8.4.6 Zero-Delay Mode Synchronization
      7. 8.4.7 DPLL Programmable Phase Delay
    5. 8.5 Programming
      1. 8.5.1 Interface and Control
      2. 8.5.2 I2C Serial Interface
        1. 8.5.2.1 I2C Block Register Transfers
      3. 8.5.3 SPI Serial Interface
        1. 8.5.3.1 SPI Block Register Transfer
      4. 8.5.4 Register Map Generation
      5. 8.5.5 General Register Programming Sequence
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Device Start-Up Sequence
      2. 9.1.2 Power Down (PD#) Pin
      3. 9.1.3 Strap Pins for Start-Up
      4. 9.1.4 Pin States
      5. 9.1.5 ROM and EEPROM
      6. 9.1.6 Power Rail Sequencing, Power Supply Ramp Rate, and Mixing Supply Domains
        1. 9.1.6.1 Power-On Reset (POR) Circuit
        2. 9.1.6.2 Powering Up From a Single-Supply Rail
        3. 9.1.6.3 Power Up From Split-Supply Rails
        4. 9.1.6.4 Non-Monotonic or Slow Power-Up Supply Ramp
      7. 9.1.7 Slow or Delayed XO Start-Up
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curves
    3. 9.3 Do's and Don'ts
    4. 9.4 Power Supply Recommendations
      1. 9.4.1 Power Supply Bypassing
    5. 9.5 Layout
      1. 9.5.1 Layout Guidelines
      2. 9.5.2 Layout Example
      3. 9.5.3 Thermal Reliability
  10. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Development Support
        1. 10.1.1.1 Clock Tree Architect Programming Software
        2. 10.1.1.2 Texas Instruments Clocks and Synthesizers (TICS) Pro Software
        3. 10.1.1.3 PLLatinum™ Simulation Tool
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Support Resources
    5. 10.5 Trademarks
    6. 10.6 Glossary
    7. 10.7 Electrostatic Discharge Caution
  11. 11Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.2.2.2 Cascaded DPLL Operation

Figure 8-4 shows an example where DPLL1 and DPLL2 are in cascaded mode from DPLL3/APLL3. In this example, DPLL3 is the main synchronization DPLL, DPLL1, and DPLL2 are cascaded DPLLs.

Cascading of DPLLs provides clean, low jitter output clocks synchronized with DPLL3. When all enabled DPLLs and APLLs are locked, all enabled outputs will be synchronized to the reference selected by the main synchronization DPLL.

When no valid reference input is present, APLL1, APLL2, and APLL3 lock their VCO frequencies to the external XO input and operate in free-run mode .

When a valid DPLL reference input is detected, the main synchronization DPLL3 begins lock acquisition. The DPLL3 TDC compares the phase of the selected reference input clock with the FB divider clock from the respective VCO3 and generates a digital correction word corresponding to the phase error. The correction word is filtered by the DLF, and the DLF output adjusts the APLL N divider numerator to pull the VCO frequency into lock with the reference input.

DPLL3 lock status may not necessarily impact DPLL1 and DPLL2 lock status. If APLL3 is in free-run mode or holdover mode, and the VCBO frequency offset ppm value is still withing the valid reference conditions for DPLL1 and DPLL2, then cascaded DPLL1, APLL1, DPLL2, and APLL2 are able to maintain lock status while tracking the same frequency offset as APLL3. Note in cascaded DPLL mode, the best jitter performance and frequency stability will be achieved after DPLL3 has locked.

Figure 8-4 DPLL Cascaded Mode